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/packages cannot be represented as URI - pdffigures2

The scala package contains core types like Int, Float, Array or Option which are accessible in all Scala compilation units without explicit qualification or imports. As I understand, TrieMap.getOrElseUpdate is still not truly atomic, and this fixes only returned result (it could return different instances for different callers before this fix), so the updater function still might be called several times, as documentation (for 2.11.7) says: Note: This method will invoke op at most once. ms getOrElseUpdate (k, d) If key k is defined in map ms, return its associated value. Otherwise, update ms with the mapping k -> d and return d. Removals: ms -= k: Removes mapping with key k from ms as a side effect and returns ms itself.

Getorelseupdate scala

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ms --= ks // not possible with Int counts.getOrElseUpdate(key, 0) += 1 // but with a modifiable counter counts.getOrElseUpdate(key, new Counter).increment Somehow I'm always expecting to have the following functionality with a mutable map (somewhat similar to transform but without returning a new collection and on a specific key with a default value): Note: getOrElseUpdate is not an atomic operation in EhCache and is implemented as a get followed by computing the value, then a set. This means it’s possible for the value to be computed multiple times if multiple threads are calling getOrElse simultaneously. .getOrElseUpdate makes it convenient to use a mutable Map as a cache: the second parameter to .getOrElseUpdate is a lazy "by-name" parameter, and is only evaluated when the key is not found in the Map. This provides the common "check if key present, if so return value, otherwise insert new value and return that" workflow built in. As discussed above, the getOrElseUpdate () method retrieves the specified tweets from the cache if they exist, otherwise, it calls our wrapper for the Twitter API to retrieve the latest values. This is a very common usage pattern for any cache.

Scala: HashMap med olika datatyper för olika nycklar möjligt?

runtime.MacroRuntimes.standardMacroRuntime(MacroRuntimes. Runner.main(Runner.scala) Caused by: java.awt.HeadlessException at getOrElseUpdate(MapLike.scala:189) at scala.collection.mutable.AbstractMap. Feb 11, 2021 HashMap.getOrElseUpdate(HashMap.scala:86) ~[scala-library-2.12.10.jar:?] at org.neo4j.cypher.internal.compiler.helpers.

Scala: HashMap med olika datatyper för olika nycklar möjligt?

Getorelseupdate scala

Li HaoyiLi Haoyi graduated from MIT with a degree in Computer Science and Engineering, and since then has been a major contributor to the Scala community. The last item among the control abstraction is the for expression. The Scala's for loop is a swiss army knife of iterations.

The scala package contains core types like Int, Float, Array or Option which are accessible in all Scala compilation units without explicit qualification or imports. As I understand, TrieMap.getOrElseUpdate is still not truly atomic, and this fixes only returned result (it could return different instances for different callers before this fix), so the updater function still might be called several times, as documentation (for 2.11.7) says: Note: This method will invoke op at most once.
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retronym merged 3 commits into scala: 2.12.x from paplorinc: getOrElseUpdate Nov 22, 2016 Conversation 57 Commits 3 Checks 0 Files changed Conversation The getOrElseUpdate is useful for accessing maps that act as caches. Say you have an expensive computation triggered by invoking a function f : scala> def f(x: String ) = { igreenfield commented on Jan 28, 2018. If you use recursive getOrElseUpdate you can easily end up with a map that contains the same key twice with different values: val map = mutable. Map [ String, String ] () map.getOrElseUpdate ( "key", { map.getOrElseUpdate ( "key", "value1" ) "value2" }) map.

ms getOrElseUpdate (k, d) If key k is defined in map ms, return its associated value. Otherwise, update ms with the mapping k -> d and return d.
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/packages cannot be represented as URI - pdffigures2

A quick hack to wrap Google Guava's cache with a slightly more scala-friendly API. The main goal is to have a getOrElseUpdate method that is actually thread safe, unlike the one on Scala's ConcurrentMap. [Redirected to scala-language since I'm not on scala-user.] Someone asked me recently why I'm against extending Function1 casually.


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Error:scalac: Error: scala.collection.immutable - Element-ui

Avoid allocating Map1-4 during building the result if the size of the grouped exceeds 4. This is the documentation for the Scala standard library. Package structure .